1. Field of the Invention
The disclosure relates in general to a method for manufacturing semiconductor device and structure manufactured by the same, more particularly to a method for manufacturing three-dimensional (3D) semiconductor device using thin hard mask and structure manufactured by the same.
2. Description of the Related Art
A nonvolatile semiconductor memory device is typically designed to securely hold data even when power is lost or removed from the memory device. Various types of nonvolatile memory devices have been proposed in the related art. Also, manufactures have been looking for new developments or techniques combination for stacking multiple planes of memory cells, so as to achieve greater storage capacity. For example, several types of multi-layer stackable thin-film transistor (TFT) NAND-type flash memory structures have been proposed. Various semiconductor devices with three-dimensional (3D) stacked structures, having single-gate unit cells, double gate unit cells or surrounding gate unit cells, have been provided.
It is desirable to develop a semiconductor device with 3D stacked structure not only with larger number of multiple planes being stacked to achieve greater storage capacity, but also with smaller unit cells and excellent electrical properties (such as reliability and stability of data storage), so that the smaller memory elements still can be erased and programmed effectively. Moreover, the reduced dimensions of the semiconductor devices with 3D stacked structures might create the thinner and higher patterns. The thin and high patterns (ex: an aspect ratio of a height of the pattern to its width is too high) of the 3D stacked structure would be fallen down or bended easily during the manufacturing process. Therefore, it is one of the important goals to develop the related procedures for making the thinner but solid patterns of the device with 3D stacked structure. Accordingly, it is desirable to fabricate a semiconductor device with 3D stacked structure with high speed and solid construction, and that device is also manufactured by not complicated manufacturing process thereby diminishing the manufacturing cost.